enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Bond energy - Wikipedia

    en.wikipedia.org/wiki/Bond_energy

    [1] The bond dissociation energy (enthalpy) [4] is also referred to as bond disruption energy, bond energy, bond strength, or binding energy (abbreviation: BDE, BE, or D). It is defined as the standard enthalpy change of the following fission: R—X → R + X. The BDE, denoted by Dº(R—X), is usually derived by the thermochemical equation,

  3. Standard enthalpy of reaction - Wikipedia

    en.wikipedia.org/wiki/Standard_enthalpy_of_reaction

    If the enthalpies for each step can be measured, then their sum gives the enthalpy of the overall single reaction. [11] Finally the reaction enthalpy may be estimated using bond energies for the bonds which are broken and formed in the reaction of interest. This method is only approximate, however, because a reported bond energy is only an ...

  4. Activation energy - Wikipedia

    en.wikipedia.org/wiki/Activation_energy

    In the Arrhenius model of reaction rates, activation energy is the minimum amount of energy that must be available to reactants for a chemical reaction to occur. [1] The activation energy (E a) of a reaction is measured in kilojoules per mole (kJ/mol) or kilocalories per mole (kcal/mol). [2] Activation energy can be thought of as the magnitude ...

  5. Binding energy - Wikipedia

    en.wikipedia.org/wiki/Binding_energy

    Bond energy and bond-dissociation energy are measures of the binding energy between the atoms in a chemical bond. It is the energy required to disassemble a molecule into its constituent atoms. This energy appears as chemical energy, such as that released in chemical explosions, the burning of chemical fuel and biological processes. Bond ...

  6. Ionic bonding - Wikipedia

    en.wikipedia.org/wiki/Ionic_bonding

    Ionic bonds have high bond energy. Bond energy is the mean amount of energy required to break the bond in the gaseous state. Most ionic compounds exist in the form of a crystal structure, in which the ions occupy the corners of the crystal. Such a structure is called a crystal lattice.

  7. Bond cleavage - Wikipedia

    en.wikipedia.org/wiki/Bond_cleavage

    The bond-dissociation energy of a bond is the amount of energy required to cleave the bond homolytically. This enthalpy change is one measure of bond strength. The triplet excitation energy of a sigma bond is the energy required for homolytic dissociation, but the actual excitation energy may be higher than the bond-dissociation energy due to ...

  8. Exothermic reaction - Wikipedia

    en.wikipedia.org/wiki/Exothermic_reaction

    An energy profile of an exothermic reaction. In an exothermic reaction, by definition, the enthalpy change has a negative value: ΔH = H products - H reactants < 0. where a larger value (the higher energy of the reactants) is subtracted from a smaller value (the lower energy of the products). For example, when hydrogen burns: 2H 2 (g) + O 2 (g ...

  9. Thermochemical equation - Wikipedia

    en.wikipedia.org/wiki/Thermochemical_equation

    In thermochemistry, a thermochemical equation is a balanced chemical equation that represents the energy changes from a system to its surroundings.One such equation involves the enthalpy change, which is denoted with In variable form, a thermochemical equation would appear similar to the following: